Chip Somodevilla/Getty Images(WASHINGTON) -- Republican Sens. Marco Rubio and Rand Paul may not be perfect together but they are perfect in the eyes of the American Conservative Union.

Rubio from Florida and Paul from Kentucky were given a "perfect 100 percent" score for their voting records, earning them the group's coveted "Defenders of Liberty" designation.

The American Conservative Union, which is sponsoring next month's Conservative Political Action Conference (CPAC) featuring 2012 GOP presidential nominee Mitt Romney, based their ranking on lawmakers' votes regarding fiscal, foreign and social policies.

Rubio and Paul have both been mentioned as possible Republican standard bearers in 2016. While Rubio has been coy about his long-range intentions, Paul has indicated he might seek the Republican nod.

On the other side of the scale, the American Conservative Union gave Democrats Chuck Schumer of New York, Dick Durbin of Illinois, Al Franken of Minnesota and Senate Majority Leader Harry Reid a "zero percent" score, designating them as "true liberals."